The present invention relates to medical instruments and, more particularly, medical instruments for use in a laparoscopy.
Instruments used to grasp, hold and/or compress tissue, body parts or surgical substances--such as forceps or clamps--are well-known for use in open surgical procedures. In a laparoscopy, however, these medical instruments must be inserted through a slender cylindrical cannula--or trocar--to access the patient's abdominal cavity. The instruments designed for open surgeries are not sufficiently slender to pass through the trocar and are thus ill-suited for laparoscopic procedures.
Forceps and other medical instruments have been recently developed for use in a laparoscopy and include an elongate body that is extendable through a trocar into the patient and tips that are narrower than the elongate body. These instruments typically manipulate the tips from the proximal end thereof (i.e., the end nearest the surgeon) in the simplest fashion to translate motion to the distal end. For example, some laparoscopic instruments include an operating rod or sleeve that is pressed forwardly into a portion of the elongate body, which is held between the fingers of the surgeon, similar to a plunger on a conventional syringe to open and close the tips. Other laparoscopic instruments manipulate their tips by a pistol-like handle that is oriented at a 90.degree. angle from the longitudinal axis of the body of the instrument.
While these instruments have proven to be generally satisfactory in opening and closing the tips, such actuating mechanisms do not provide the surgeon with the precise control over the grasping or clamping tip that is required in complex surgeries since these actuating mechanisms are not longitudinally aligned with the tips and the tips do not parallel the motion of the surgeon's fingers on the actuating mechanisms. The most important tools at the surgeon's disposal in an open surgery are his fingers, which enable the surgeon to feel around the abdominal cavity and move organs, etc. The need for an instrument that mimics the surgeon's fingers has become increasingly apparent with the expanding acceptance of laparoscopy for more complex abdominal operations, such as on the large intestine.
Further, the grasping tips on the present laparoscopic instruments pivot about a single pivot point, which may be problematical since tissue located near the pivot point can be pinched. Also, attempts to move or twist the intestine may result in a tear because of this simplistic pivot point and also because of the relatively sharp corners on the present laparoscopic instruments.